Fin assembly

ABSTRACT

A fin assembly for a board includes a fixing element adapted to be embedded into a lower surface of the board and a fin. The fixing element includes a cavity, at least one projection extending upwardly in the cavity from the fixing element and towards an opening of the cavity, and a fixing member received by the fixing element and engageable with the projection. The fin has a formation projecting from an end surface of the fin and adapted to be received within the cavity. The formation includes a free end and at least one recessed portion located between the free end and the end surface of the fin. When the fixing formation is received within the fixing cavity, the fixing member may urge the projection against the recessed portion to thereby secure the fin to the board.

FIELD OF THE INVENTION

[0001] This invention relates to a fin assembly. In particular, the invention relates to a fin assembly for watercraft such as surfboards.

[0002] The invention will be described by way of example with reference to surfboards. However, it should be appreciated that this description is by way of example only and that the fin assembly of the invention may be used with other watercraft such as sailing craft, paddle skis, surf skis and the like. For convenience, such watercraft will hereinafter be collectively referred to as “boards”.

DESCRIPTION OF THE PRIOR ART

[0003] Surfboards include a body having a foam core of buoyant material covered with a skin of fibre-reinforced resin material. The board includes an upper surface for supporting a rider, a lower surface and one or more fins secured to and projecting from the lower surface. Traditionally, the fins have been permanently mounted to the body of the surfboard by being fibreglassed thereto.

[0004] A disadvantage of permanently mounting fins onto a surfboard is that they cannot readily be removed and replaced if, for example, they are damaged. Further, fins having different performance characteristics are available and there are advantages in being able to readily remove and replace the fins on a board so that the board exhibits different riding characteristics. Also, the presence of fins on a board renders the board somewhat difficult to transport and store and it is advantageous to be able to remove the fins to allow the board to be more readily stored and transported. This is not possible where fins are permanently mounted to the lower surface of the board.

[0005] Removable fin assemblies have previously been proposed. Australian patents 665804 and 707856 disclose inventions relating to removable fin fixing systems.

[0006] It is an object of the present invention to provide a fin assembly which at least offers a viable alternative to the removable fin fixing systems of the above-mentioned Australian patents.

SUMMARY OF THE INVENTION

[0007] According to an aspect of the present invention there is provided a fin assembly for a board, the fin assembly including:

[0008] a fixing element adapted to be embedded into a lower surface of the board;

[0009] a fixing cavity extending into the fixing element;

[0010] at least one projection located inside the fixing cavity and extending upwardly from the fixing element towards an opening of the cavity;

[0011] a fixing member received by the fixing element and engageable with the projection;

[0012] a fin attachable to the board and having an end surface which is located adjacent to the lower surface of the board when the fin is attached to the board; and

[0013] a fixing formation projecting from the end surface of the fin, wherein the fixing formation is adapted to be received within the fixing cavity, and wherein the fixing formation includes a free end and at least one recessed portion located between the free end and the end surface of the fin, whereby, when the fixing formation is received within the fixing cavity, the fixing member may urge the projection against the recessed portion to thereby secure the fin to the board.

[0014] In a preferred form, the recessed portion tapers from the free end towards the end surface of the fin to thereby provide an inclined abutment surface, whereby, when the fixing formation engages with the fixing cavity, the fixing member may urge the projection against the inclined abutment surface to thereby secure the fin to the board. Alternatively, the recessed portion may be in the form of a curved recess.

[0015] As mentioned above, the fixing element has at least one projection located inside the fixing cavity and extending upwardly from the fixing element towards an opening of the cavity. The projections are preferably arranged such that they are located adjacent to a sidewall of the cavity, and such that they may be urged away from the sidewall by the fixing member. It is preferred that there are two projections arranged at spaced locations along the fixing element. The projections may extend upwardly from a base of the fixing element.

[0016] Where there are a plurality of projections, each of the projections may have associated with it a respective fixing member. In a preferred embodiment, the fixing members comprise fasteners extending into the fixing element at an inclined angle relative to the fixing element. Each fixing member may be received by an associated inclined passage which extends through the fixing element such that the fixing members may engage the projections and urge the projections against the recessed portions. Clearly, where the assembly of the invention has a plurality of projections, the fixing formation is provided with a corresponding number of recessed portions with each recessed portion having an associated projection. Where the fixing element is provided with two projections, it is preferred that the fixing formation is provided with two recessed portions which are separated by a central portion having parallel side faces. Apertures may be provided extending through the central portion of the fixing formation. A peripheral flange may extend from the fixing element and extensions may project outwardly from opposed extremes of the peripheral flange, wherein the extensions are adapted to control the amount by which the fixing element is embedded into the board.

[0017] In order that the invention may be more fully understood and put into practice, a preferred embodiment thereof will now be described with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0018]FIG. 1 is a perspective view of a fixing element according to an embodiment of the invention;

[0019]FIG. 2 is an exploded perspective view of the fixing element illustrated in FIG. 1 and of a fin securable to the fixing element;

[0020]FIG. 3 is a transverse cross-sectional view of the fixing element illustrated in FIG. 1;

[0021]FIG. 4 is a transverse cross-sectional view of the fixing element which illustrates the position and state it assumes when initially mounted relative to a board to which it is to be secured;

[0022]FIG. 5 is a transverse cross-sectional view of the fixing element like that illustrated in FIG. 4 but shown in its final state when secured to the board;

[0023]FIG. 6 is an enlarged view of a fixing formation which extends outwardly from an end surface of the fin; and

[0024]FIG. 7 is an exploded perspective view of a fin and a portion of a board to which a fixing element has been secured.

DETAILED DESCRIPTION

[0025]FIG. 1 shows a fixing element 10. The fixing element 10 in this embodiment consists of three lobes 11, 12 and 13 that each have a substantially cylindrical appearance. At an upper end of these lobes a peripheral flange 14 extends around and beyond the upper surface 19 of the lobes 11, 12 and 13. Extensions 15, 16 project outwardly from opposed extremes of the peripheral flange 14. A lower face 17, 18 of the extensions 15, 16 are each at a location which is coincident with the surface 19 from which the flange 14 extends.

[0026] A fixing cavity 20 extends into the fixing element 10. The fixing cavity 20 is adapted to receive a fixing formation which is described below. In the regions of the lobes 11 and 13, upwardly extending projections 21 and 22 are visible in the fixing cavity 20. Inclined passages 23 and 24 extend through the lobes 11 and 13 towards the projections 21 and 22. Ramped lead-in portions 25 and 26 are provided in the flange 14 at a location adjacent the inclined passages 23 and 24.

[0027]FIG. 2 is an exploded view of the fixing element 10 and a portion of a fin 30. The fin 30 has a fin body 31 with an end surface 32 and a fixing formation 33 extending outwardly from the end surface 32. The formation 33 has a central portion 34 between locations 35 and 36 which consists of front and rear faces which are parallel to one another. Opposed end portions 37 and 38 of the fixing formation 33 are tapered such that the thickness of these end portions is greater at an outer extremity 39 than at an inner extremity 40. In this way, portions 37, 38 effectively provide recesses.

[0028]FIG. 3 is a transverse cross-sectional view of the fixing element 10 taken across the element 10 at the location of the ramped lead-in portion 25. In this view a base portion 45 is shown from which projection 21 extends upwardly and adjacent to a sidewall of the fixing cavity 20. Inclined passage 23 is visible in this view. The passage 23 is adapted to receive a fixing member in the form of a fastener 46. When the fastener 46 is driven into the passage 23 it may contact the projection 21 and urge that projection away from the sidewall of the fixing cavity 20.

[0029]FIG. 4 shows a view not unlike that shown in FIG. 3. However, in FIG. 4 the fixing element 10 is shown received within a recess 47 provided in a board 48. The board 48 is made from a core of foam material 49 which has an outer skin 50. The fixing element 10 is secured within the recess 47 by a suitable material such as a resin 51. The presence of resin 51 ensures that the fixing element 10 is effectively permanently secured to the board 48. The oppositely directed extensions 15 and 16 (not visible in this view) control the depth to which the fixing element 10 is received within the recess 47. Once the resin 51 has set, the flange 14 is removed from the fixing element 10 so that the surface 19 of the fixing element 10 is flush with the outer surface of the skin 50 as shown in FIG. 5.

[0030]FIG. 6 is an enlarged view of the fixing formation 33. The central portion 34 delineated by locations 35 and 36 is clearly visible in this view. The opposed tapered end portions 37, 38 are located on either side of the central portion 34 and are thicker in the region of extremity 39 than extremity 40 where the fixing formation 33 connects to the body 31 of the fin 30. Apertures 52 and 53 extend through the fixing formation 33.

[0031]FIG. 7 shows the stem of a board 48 with the fixing element 10 embedded and secured within the board 48 and with the flange 14 (shown in FIG. 1) removed therefrom. The fixing element 10 has its surface 19 flush with the outer skin 50 of the board 48. Projections 21 and 22 described previously are visible in this view. The outer ends of passages 23 and 24 are also shown.

[0032] The fin 30 with fixing formation 33 projecting outwardly from end surface 32 is also visible and the fixing formation 33 is shown in the position it would assume immediately prior to its insertion into the cavity 20.

[0033] When the fixing formation 33 is inserted into the cavity 20, the end surface 32 abuts the outer skin 50 of the board 48. The fasteners 46 (see FIG. 3) located within the inclined passages 23, 24 (see FIG. 7) are then driven through the passages 23, 24 until the upstanding projections 21, 22 are directed against the tapered portions 37, 38 to thereby wedge the fixing formation 33 securely within the cavity 20 so that the fin 30 is securely mounted relative to the board 48. If necessary, the fin 30 may readily be removed from the board 48 simply by retracting the fasteners 46 to allow the projections 21, 22 to move away from the tapered end portions 37, 38 of the fixing formation 33. Once the projections 21, 22 are no longer wedged against the tapered end portions 37, 38, the fin 30 may then be separated from the board 48.

[0034] The foregoing describes only one embodiment of the present invention and modifications, obvious to those skilled in the art, can be made thereto without departing from the scope of the present invention. For example, the projections 21, 22 may be located on opposite sides of the fixing cavity 20 so that they are able to press against the fixing formation 33 in opposite directions. Further, the fixing element 10 may have only one projection 21 or 22. Also, instead of end portions 37 and 38 being tapered, they could each be in the form of a curved recess. 

1. A fin assembly for a board, the fin assembly including: a fixing element adapted to be embedded into a lower surface of the board; a fixing cavity extending into the fixing element; at least one projection located inside the fixing cavity and extending upwardly from the fixing element towards an opening of the cavity; a fixing member received by the fixing element and engageable with the projection; a fin attachable to the board and having an end surface which is located adjacent to the lower surface of the board when the fin is attached to the board; and a fixing formation projecting from the end surface of the fin, wherein the fixing formation is adapted to be received within the fixing cavity, and wherein the fixing formation includes a free end and at least one recessed portion located between the free end and the end surface of the fin, whereby, when the fixing formation is received within the fixing cavity, the fixing member may urge the projection against the recessed portion to thereby secure the fin to the board.
 2. The fin assembly of claim 1, wherein the recessed portion is in the form of a curved recess.
 3. The fin assembly of claim 1, wherein the recessed portion tapers from the free end towards the end surface of the fin to thereby provide an inclined abutment surface, whereby, when the fixing formation is received within the fixing cavity, the fixing member may urge the projection against the inclined abutment surface to thereby secure the fin to the board.
 4. The fin assembly of claim 1, wherein the projections are located adjacent to a sidewall of the cavity such that they may be urged away from the sidewall by the fixing member.
 5. The fin assembly of claim 1 having at least two projections arranged at spaced locations along the fixing element.
 6. The fin assembly of claim 1, wherein the projections extend upwardly from a base of the fixing element.
 7. The fin assembly of claim 1, wherein each projection has an associated fixing member.
 8. The fin assembly of claim 1, wherein each fixing member is in the form of a fastener extending into the fixing element at an inclined angle relative to the fixing element.
 9. The fin assembly of claim 8, wherein each fixing member is received by an associated inclined passage which extends through the fixing element such that the fixing members may engage the projections and urge the projections against the recessed portions.
 10. The fin assembly of claim 1, wherein each said recessed portion of the fixing formation has an associated said projection.
 11. The fin assembly of claim 1, wherein the fixing formation is provided with two recessed portions which are separated by a central portion having parallel side faces.
 12. The fin assembly of claim 1, including at least one aperture extending through the fixing formation.
 13. The fin assembly of claim 1, including a peripheral flange extending from the fixing element.
 14. The fin assembly of claim 13, including extensions projecting outwardly from opposed extremes of the peripheral flange, wherein the extensions limit the extent to which the fixing element may be embedded into the board. 